6420801979 has 2 divisors, whose sum is σ = 6420801980. Its totient is φ = 6420801978.

The previous prime is 6420801977. The next prime is 6420801991. The reversal of 6420801979 is 9791080246.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6420801979 - 2¹ = 6420801977 is a prime.

Together with 6420801977, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (6420801977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3210400989 + 3210400990.

It is an arithmetic number, because the mean of its divisors is an integer number (3210400990).

Almost surely, 2^6420801979 is an apocalyptic number.

6420801979 is a deficient number, since it is larger than the sum of its proper divisors (1).

6420801979 is an equidigital number, since it uses as much as digits as its factorization.

6420801979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 217728, while the sum is 46.

The square root of 6420801979 is about 80129.9068949915. The cubic root of 6420801979 is about 1858.6449045193.

The spelling of 6420801979 in words is "six billion, four hundred twenty million, eight hundred one thousand, nine hundred seventy-nine".